Why is this medication prescribed?

Oxybutynin is used to treat overactive bladder (a condition in which the bladder muscles contract uncontrollably and cause frequent urination, urgent need to urinate, and inability to control urination) control urgent, frequent, or uncontrolled urination in people who have overactive bladder (a condition in which the bladder muscles have uncontrollable spasms), Oxybutynin is also used to control bladder muscles in adults and children older than 6 years of age with spina bifida (a disability that occurs when the spinal cord does not close properly before birth), or other nervous system conditions that affect the bladder muscles. Oxybutynin is in a class of medications called anticholinergics/antimuscarinics. It works by relaxing the bladder muscles.

How should this medicine be used?

Oxybutynin comes as a tablet, a syrup, and an extended-release (long-acting) tablet to take by mouth. The tablets and syrup are usually taken two to four times a day. The extended-release tablet is usually taken once a day with or without food. Take oxybutynin at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take oxybutynin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the extended-release tablets whole with plenty of water or other liquid. Do not split, chew, or crush the extended-release tablets. Tell your doctor if you cannot swallow tablets.

Use a dose-measuring spoon or cup to measure the correct amount of liquid for each dose, not a household spoon.

Your doctor may start you on a low dose of oxybutynin and gradually increase your dose, not more than once every week.

Oxybutynin may control your symptoms but will not cure your condition. Continue to take oxybutynin even if you feel well. Do not stop taking oxybutynin without talking to your doctor.

You may notice some improvement in your symptoms within the first 2 weeks of your treatment. However, it may take 6–8 weeks to experience the full benefit of oxybutynin. Talk to your doctor if your symptoms do not improve at all within 8 weeks.

Other uses for this medicine

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking oxybutynin,

tell your doctor and pharmacist if you are allergic to oxybutynin, any other medications, or any of the ingredients in oxybutynin tablets, extended-release tablets, or syrup. Ask your doctor or pharmacist for a list of the ingredients.

tell your doctor if you have or have ever had narrow angle glaucoma (a serious eye condition that may cause vision loss), any condition that stops your bladder from emptying completely, or any condition that causes your stomach to empty slowly or incompletely. Your doctor may tell you not to take oxybutynin.

tell your doctor if you have or have ever had ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum); gastroesophageal reflux disease (GERD; condition in which the contents of the stomach back up into the esophagus and cause pain and heartburn); hiatal hernia (condition in which a portion of the wall of the stomach bulges outward, and may cause pain and heartburn); hyperthyroidism (condition in which there is too much thyroid hormone in the body); myasthenia gravis (a disorder of the nervous system that causes muscle weakness); fast or irregular heartbeat; high blood pressure; benign prostatic hypertrophy (BPH, enlargement of the prostate, a male reproductive organ); or heart, liver, or kidney disease.

tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking oxybutynin, call your doctor.

talk to your doctor about the risks and benefits of taking oxybutynin tablets or syrup if you are 65 year of age or older. Older adults should not usually take oxybutynin tablets or syrup because they are not as safe and may not be as effective as other medications that can be used to treat the same condition.

if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking oxybutynin.

you should know that this medication may make you drowsy or cause blurred vision. Do not drive a car or operate machinery until you know how this medication affects you.

talk to your doctor about the safe use of alcohol while you are taking this medication. Alcohol can make the side effects from oxybutynin worse.

you should know that oxybutynin may make it harder for your body to cool down when it gets very hot. Avoid exposure to extreme heat, and call your doctor or get emergency medical treatment if you have fever or other signs of heat stroke such as dizziness, nausea, headache, confusion, and fast pulse after you are exposed to heat.

What special dietary instructions should I follow?

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.

What should I do if I forget a dose?

If you are taking the tablet or syrup, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

If you are taking the extended-release tablet and you remember more than 8 hours before it is time for the next dose, take the missed dose right away. However, if your next dose is due in less than 8 hours, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for the missed one.

What side effects can this medication cause?

Oxybutynin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

dry mouth

blurred vision

dry eyes, nose, or skin

stomach pain

constipation

diarrhea

nausea

heartburn

gas

change in ability to taste food

headache

dizziness

weakness

confusion

sleepiness

difficulty falling asleep or staying asleep

nervousness

flushing

swelling of the hands, arms, feet, ankles, or lower legs

back or joint pain

Some side effects can be serious. If you experience the following symptom, call your doctor immediately or get emergency medical treatment:

rash

hives

swelling of the eyes, face, lips, tongue, or throat

hoarseness

difficulty breathing or swallowing

frequent, urgent, or painful urination

fast, irregular, or pounding heartbeat

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].

Oxybutynin may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

Symptoms of overdose may include the following:

restlessness

uncontrollable shaking of a part of your body

irritability

seizures

confusion

hallucinations (seeing things or hearing voices that do not exist)

flushing

fever

irregular heartbeat

vomiting

difficulty urinating

slowed or difficult breathing

inability to move

coma (loss of consciousness for a period of time)

memory loss

agitation

wide pupils (black circles in the centers of the eyes)

dry skin

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

If you are taking the extended-release tablet, you may notice something that looks like a tablet in your stool. This is just the empty tablet shell and does not mean that you did not get your complete dose of medication.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.